Menu
Is there any way to speed up getting an array size in C?
Typing out sizeof(array)/sizeof(int) every time gets old. Do any C libraries have something like .length or is there some way I can define sizeof(array)/sizeof(int) as a shorter constant of some sort (possible also using dot notation)?
690
Using the sizeof() operator and using pointer arithmetic. The sizeof() operator in C calculates the size of passed variables or datatype in bytes. Therefore to find the array's length, divide the total array size by the size of one datatype that you are using.
With the help of the length variable, we can obtain the size of the array. Examples: int size = arr[]. length; // length can be used // for int[], double[], String[] // to know the length of the arrays.
To find the length of the array we have to use sizeof() function. The sizeof() function in C calculates the size in bytes of the passed variable or data type. To calculate the length of array in C, first, calculate the total size of the array and then calculate the size of the data type.
You can declare an array without a size specifier for the leftmost dimension in multiples cases: as a global variable with extern class storage (the array is defined elsewhere), as a function parameter: int main(int argc, char *argv[]) . In this case the size specified for the leftmost dimension is ignored anyway.
You can use sizeof(array)/sizeof(*array) and make a macro.
#define length(array) (sizeof(array)/sizeof(*(array)))
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
